There could be ways to support doorbell mapping with !MMU, but things
like pgprot_noncached are not universally supported.
Fixable, but just disable this for now.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
        return 0;
 }
 
+#ifdef CONFIG_MMU
 static vm_fault_t vhost_vdpa_fault(struct vm_fault *vmf)
 {
        struct vhost_vdpa *v = vmf->vma->vm_file->private_data;
        vma->vm_ops = &vhost_vdpa_vm_ops;
        return 0;
 }
+#endif /* CONFIG_MMU */
 
 static const struct file_operations vhost_vdpa_fops = {
        .owner          = THIS_MODULE,
        .release        = vhost_vdpa_release,
        .write_iter     = vhost_vdpa_chr_write_iter,
        .unlocked_ioctl = vhost_vdpa_unlocked_ioctl,
+#ifdef CONFIG_MMU
        .mmap           = vhost_vdpa_mmap,
+#endif /* CONFIG_MMU */
        .compat_ioctl   = compat_ptr_ioctl,
 };